A method of manufacturing a textured food product and a textured food product

ABSTRACT

A method of manufacturing a textured food product comprising the steps of preparing a slurry comprising dry matter and water, wherein the dry matter comprises 1. at least 35% by weight legume protein, 2. 10% to 45% by weight oat bran, whole grain oat flour or a mixture thereof, and 3. 2% t 35% by weight of the dry matter of oat protein, of which 2. and 3. must always add up to no more than 65% by weight. The slurry further comprises water 20%-80% by weight of the weight of the dry matter. The method further includes cooking the slurry in an extruder cooker and extruding the cooked slurry to form the textured food product.

FIELD OF THE INVENTION

The present invention relates to methods for manufacturing of texturedfood products.

TECHNICAL BACKGROUND

Vegetable-based protein-rich products offer many benefits and advantagesto consumers. Protein-rich plant food offers a sustainable way offulfilling the daily protein requirements. In addition to the proteins,plants are high in bioactive compounds such as complex carbohydrates,which are widely recognized as being healthful. The majority of theWestern consumers would like to prefer a plant-based diet due to itshealthiness and ecological concern. However, many consumers find itdifficult to keep their daily protein intake sufficient due to thenarrow and inconvenient offering of proteinous plant products.

Protein bar snack products are a convenient choice, but are limited tosyrup-based taste profiles and have sandy structure. The main-courseplant protein foods in the markets are often sold as dry, requiring timeand certain knowledge to process them to an edible meal. From theviewpoint of ingredients commercially available as ready-to-eatproducts, vegetarian minded consumers have also only few choices. Mostof the ready-to-eat products containing plant protein are based on soyaor wheat gluten, which some consumers like to avoid due to allergy,ecological or ethical reasons or GMO related concerns.

One of the challenges with soya products widely utilized as a plantbased main course is the beany taste of the products that makes someconsumers to search for alternatives.

Objective of the Invention

An objective of the invention is to improve the nutritional value of atextured food product manufactured by cooking and extruding legumeprotein.

The dependent claims describe advantageous embodiments of the method.

Advantages of the Invention

The method of manufacturing a textured food product comprises the stepsof:

-   -   preparing a slurry,        -   i) the dry matter of which comprises:            -   1. at least 35 weight-% legume protein,            -   2. 10 to 45 weight-% oat bran, whole grain oat flour or                a mixture thereof, and            -   3. 2 to 35 (or 5 to 35) weight-% oat protein,            -   of which 2. and 3. must always add up to no more than 65                weight-%;            -   and        -   ii) the slurry further comprising water 20-80%, preferably            30-40%, most preferably 35-40%, of the weight of the dry            matter; and    -   cooking the slurry in an extruder cooker and extruding it to        form an textured food product.

Preferably, the share of oat protein is chosen to compensate for theeffects leading to a dough-like texturation due to the share of oat branor whole grain oat flour or the mixture thereof.

The result of the method results in a textured food product having allamino acids necessary for human daily intake that cannot be synthetizedin novo. Furthermore, the resulting textured food product isheat-resistant, boiling resistant and suitable for cooking. Because ofthe extrusion, it is also ready-to-eat and can be consumed as a snack oras a main course food.

Further advantages of the method are that the porous texture will beavoided, and that the water absorption rate and hydration level of thetextured food product will be reduced thanks to the share of oat proteinas compared with a textured food product manufactured by cooking andextruding a slurry consisting of legume protein, oat bran, whole grainoat flour, or a mixture thereof, and water.

These improvements in the structure of the textured food protein improvethe acceptability of the textured food product by consumers.Furthermore, the acceptability by consumers will further be improved dueto the fact that the oat bran, or whole grain oat flour, or the mixturethereof tends to eliminate the slightly bitter taste of the legumeprotein.

Advantageously, the cooking is performed in 130-180° C., preferably in170-180° C. and most preferably in 175° C. to improve the structure ofthe textured food product. But, generally, the cooking could beperformed even at 130° C.-191° C.

Advantageously, the share of oat bran and of oat protein in the slurrymakes 40 to 60 weight-% of the dry matter content of the slurry andpreferably is chosen to make the textured food product to have aconsistency for which the resistance force of a 9.0 and 10.5 mm highsample during a compression test with a knife blade required to cut thesample is between 16 and 28 N with a penetration distance between 5.5and 8.5 mm, preferably 7.5-8.5 mm. The force required to cut thetextured food product reflects the mouthfeel (i.e. bite resistance) thatis an extremely important acceptability/quality parameter of a texturedfood product. The textured food product of according to the presentinvention gives very a acceptable mouthfeel, desirable chewiness andjuiciness, and a feeling of real food in contrast to sandy or powdery(non-continuous) structures that are assumed in the case of insolubleproteins.

Advantageously, the textured food product is further processed withwater, salt, oil and spices and brewed (or, alternatively, or inaddition to brewing, hydrated, wetted or soaked) for 2 to 12 hoursbefore additional baking, cooking or high pressure cooking. Thisprocessing step increases the moisture and improves the sensoryproperties of the textured food product. Preferably, water, oil andspices are sprayed at the textured food product and salt is sprinkled.

Advantageously, during the brewing (or, alternatively, or in addition tobrewing, during hydration, wetting or soaking), the share of water tothe textured food product is between 1:1.0 to 1:1.5 by weight, as alower water content does not provide enough moisture and a higher watercontent would ruin the desirable structure of the textured food product.

Advantageously, amylase is added to the textured food product after theextruder cooking step but before the additional high pressure cooking.This enhances sensory properties of the product.

Advantageously, the additional high pressure cooking step is performedin an autoclave or in a pressurized cooking device, preferably having apressure of at least 1.9 bar (most preferably between 1.9 and 2.1 bar),and preferably for 20 to 60 minutes, or preferably around 25 minutes, orfor 30 to 60 minutes, such as for 35 to 45 minutes. High pressurecooking further enhances the sensory properties of the product. Highpressure cooking step in an autoclave keeps the moisture of the texturedfood product in balance and further binds fibres together. High pressurecooking differs from steam heat and hypyrcritical steam heat treatmentswhich would ruin desirable structure of the textured food product.

Alternatively to the high pressure cooking step, the additional bakingor cooking step may be performed in an oven or in a steam oven, in atemperature between 110 and 130° C., most preferably around 121° C.

Preferably, the oat protein is introduced into the slurry as oat proteinfractions. This form of oat protein has turned out to produce a texturedfood product of very good sensory quality with the method according tothe invention. The at least 35% of legume protein is, preferably,computed from the protein fraction of the respective legumeprotein/legume proteins introduced into the slurry.

Preferably, the legume protein introduced into the slurry is selectedfrom at least one of the following: pea protein concentrate, pea proteinisolate, vicia faba protein concentrate, vicia faba protein isolate,peanut protein concentrate and peanut protein isolate. These are widelyavailable, have acceptable digestive qualities and are very suitable formany consumers.

Advantageously, the extrusion is carried out as protein texturationextrusion. In this case, the water feed rate during the extrusion andother extrusion parameters are preferably selected such that thetextured food product will result in relatively thick (such as between15 and 20 μm) co-aligned fibres that are bunched together.

At the time of writing, the applicant is carrying out research workwhether oat could at least partly (or even completely) be replaced withrye and/or barley. In this case, a) oat bran could be replaced (at leastpartly, or even completely) with rye bran and/or barley bran; b) wholegrain oat flour could be replaced (at least partly, or even completely)with whole grain rye flour and/or whole grain barley flour; andrespectively c) the mixture of oat bran and whole grain oat flour couldbe replaced (at least partly, or even completely) with mixture of ryebran and/or barley bran and whole grain rye flour and/or whole grainbarley flour.

LIST OF DRAWINGS

The method is explained gone through in more detail in the following byway of the exemplary embodiments and as shown in the attached drawingsin FIGS. 1 to 9, wherein:

FIG. 1 shows water absorption rates and hydration levels for extrudedtextured food products which contain certain legume proteins, 20% or 30%of oat bran and 10% of oat protein;

FIG. 2 is a diagram displaying measurement results of measurement ofresistance force vs. displacement during a compression test, for threesamples;

FIG. 3 is a photograph showing the structure of an extruded texturedfood product, the dry mass of which contains 60% of certain legumeproteins, 30% of oat bran and 10% of oat protein. The water content ofthe sample is ca. 20%.

FIG. 4 is a photograph showing the structure of an extruded texturedfood product, the dry mass of which contains 70% of certain legumeproteins and 30% of oat bran;

FIG. 5 shows the fibrous structure of an extruded textured food productwhich contains pea protein and 20% of oat bran, captured by an electronmicroscope;

FIG. 6 shows the fibrous fibrous structure of extruded textured foodproduct which contains pea protein, 20% of oat bran and 10% of oatprotein, captured by an electron microscope;

FIG. 7 shows the fibrous structure of extruded textured food productwhich contains only pea proteins captured by an electron microscope;

FIG. 8 shows the fibrous structure of extruded textured food productwhich contains pea protein, 20% oat bran and 10% of oat protein,captured by a microscope; and

FIG. 9 shows a serving of consumer-ready textured food product whichcontains contains legume protein (especially pea), oat bran and oatprotein, placed on a cutting board.

DETAILED DESCRIPTION

Oat has a relatively mild taste and is ecologically not much demanding.Indeed, oat is one of the most ecological farmed plants on the earth dueto its nitrogen-binding properties. Furthermore, it is, in contrast toother grains, usually well-tolerated, even by those with the celiacdisease. The health benefits of oat are well-known and proved. Thecomplex carbohydrate of oats, the special soluble fibre beta-glucan, hasbeen proved to be beneficial to cardiac health and blood sugar balance.Oats are also rich of plant lipids, meaning oils that are understood tobe beneficial for human health. In addition, oats contains a relativelyhigh amount of proteins with good a amino acid range. In the methoddescribed in the following, the most nutritive parts of oat kernel suchas oat bran and protein fractions are used assuring the highly nutritiveproperties of the end product.

In addition to nutritional properties, oat protein fractions have arelatively mild taste when compared to several other vegetable proteinrich flours or powders. One of the biggest problems when using legumesis the beany taste that is by the present inventors consideredundesirable.

Fibrous texture products from soy proteins are well known. The processto manufacture the products is called texturation and is based on theuse of extrusion technique. Extrusion technique in food processing hasbeen used to prepare certain pastas, breakfast cereals, pre-made cookiedough, French fries and ready-to-eat snacks. Generally, high-temperatureextrusion is used to manufacture ready-to-eat snacks, while coldextrusion is used for manufacturing pasta and related products intendedfor later cooking and consumption.

Extrusion method in pasta processing provides conveying, compacting,kneading, relaxing, and extruding forces. There is only a limited amountof heat generated by friction between the dough and metal surfaces ofthe barrel and the screw. The temperature is kept between 45° C. and 50°C. by cooling water in order to prevent the protein from denaturation,which can make the pasta soft and sticky. So in this process, theproteins are not denatured and starch is not fully gelatinized.

Starch-based extrusion has higher temperature (150° C.-170° C.) andshear pressure in the later units. Starch is released and solubilized inthe chambers (between screw and barrel). Starch carries water with highenergy in the chambers. When the material comes out from the die, thepressure is released, water evaporates, foams were formed, the structureexpands and starch gelatinizes and stabilizes the structure. Protein caninterfere the starch gel expansion. The water feed rate is between15-20%. In this process, starch is gelatinized, partially degraded,proteins are denaturized, protein-starch interactions and lipid-proteininteractions/complexes are possibly formed.

The protein texturation extrusion is different from starch-basedextrusion although the extrusion temperature is similar (120° C.-180°C.) with starch-based extrusion. Shearing by extrusion at elevatedtemperatures is the causing force for forming the fibrous proteinnetworks or texturation [1]. The recipe for protein texturation isdifferent from the starch-based extrusion. The protein content ishigher. The water feed rate is higher (limit: 20-80%; preferably 20-45%)than that of the starch-based extrusion. The screw unit design isdifferent, because the flow behavior of the fed material are different.The rheology of the protein-rich material in the barrel and screw isdifferent from that of the starch-based extrusion material. At finalstage before the die and during the die a certain design of screw unitis needed for the formation of a fibrous protein-protein networkstructure formation. During this process, starch is gelatinized, proteinis unfolded/denaturized, untangled, aligned, structured/polymerized andstabilized. There is also theory support that protein melts in certainstage of the extrusion screw unit. The protein-protein interactionforces are still not fully understood, but at least involve hydrophobicinteraction, disulfide bonding and oxidative crosslinking between aminoacids.

Since oat proteins are denser, more heat-resistant and hydrophobic asmost of the cereal proteins, they are not assumed to form fibrousstructures during extrusion like is widely known that the legumeproteins do. The flexible legume proteins orientate during shearingunder heating, and are thus forced to lose their tertiary structure andcovalent bonds. While cooling down the oriented proteins, they find newsites for covalent bonding and form fibrous irreversible structures thathave been obtained to have chewable nature widely utilized in meatanalogues.

However, when oat materials such as whole grain flour and oat bran,which are ingredients scientifically proven healthy, are textured withthe legume proteins in higher amounts (i.e. 20%), they damage thefibrous texture formation and result in dough-like textures in which achewable fibrous structure is ruined. In addition, the dough-liketexture is easily slimy that is a common challenge of oat. One challengefollowing the oat bran addition is as well the increased waterabsorption that makes the water management of the end product difficult.

We have observed that replacing 5-35 weight-% (of the dry matter of theslurry) of the legume protein fraction with oat protein fraction whenhaving 10-45 weight-% (of the dry matter of the slurry) oat bran, wholegrain oat flour, or a mixture thereof, in textured food products, thewater absorption decreases, sliminess is in control and the targetedfibrous texturation is surprisingly not transferred towards dough-liketextures.

TABLE 1 Legume protein Oat protein Pea + OB20% 64% 4.6%* Pea + OB30% 56%6.9%* Pea + OB30% + OP10% 58% 12.5** Pea + OB30% + OP20% 40% 18.9%***Oat protein from oat bran only, when it is less available due to thecell wall structure and the carbohydrates covering it **6.9% of theprotein is from oat bran and rest is from oat protein fraction.

Table 1 shows oat and legume protein concentrations from dry matter ofproducts that are used in FIGS. 1 and 2.

FIG. 1 shows water absorption rates and hydration levels of extrudedtextured food product which contains legume protein (especially pea),20% or 30% of oat bran (OB) and 10% of oat protein (OP); Waterabsorption and water hydration level are used to determine the amount ofwater absorbed by food product. As we can see from FIG. 1, when 30% ofoat bran is used in the extruded textured food product the waterabsorption rate reaches a level of more than 80% of water in less than30 minutes. Also in the extruded textured food product containing 20% ofthe oat bran, the water absorption rate reaches a level of more than 80%of water within 2 hours. However, the addition of 10% of oat protein inthe extruded textured food product containing 30% of oat bran decreasedwater absorption and hydration level surprisingly as water absorptionrate stays in under 70% water level. The effect of reduced waterabsorption and hydration level of oat protein containing product isclearly shown in FIG. 1.

FIG. 2 shows the results of a measurement performed on three texturedfood product samples with a CT3 Texture Analyzer of BrookfieldEngineering Laboratories, Inc. The CT3 Texture Analyzer was equippedwith an industrial blade having thickness of 0.23 mm.

The first sample contained pea protein (Pea) and 30% of oat bran (OB),the second sample contained pea protein and 20% of oat bran, and thethird sample contained pea protein, 30% of oat bran and 10% of oatprotein.

In the measurement, we measured the resistance forces of the samplesduring a compression test with a knife blade. The measurements werecarried out so that the CT3 Texture Analyzer was equipped with a 294.2 N(30 kg) load cell (detector sensor) and a sharp knife blade. The heightof the samples were between 9.0 and 10.5 mm. The samples were stabilizedand put horizontally on a plate and the direction of the sample wasadjusted to let the blade compress (i.e. cut) towards the cross-sectiondirection of the elongated fibre (in the length direction of the fibre).The downward speed before the blade touching the fibre was 1.5 mm/s(pre-test speed). The speed of compression when the blade touched thefibre was 1.0 mm/second (test speed) and compression went to a cuttingdepth until 99% of the height of the sample was reached.

The resistance force N of all the samples increased after the bladetouched the surface of the fibre. The increase of forces N was slowbetween 4-7 mm penetration distance d of all the samples. After 7 mmpenetration distance d, the force N increased at fastest in the thirdsample. The third sample also breaked down faster than the othersamples.

When the blade reached the penetration distance of 7.5-8.5 mm with aforce of 16-28 N, the third sample reached the main peak P which is asharp main peak, and the product was cut. The other samples thepenetration distance d was over 8.5 mm for both before the main peak Pwas reached. For the first and the seconds samples, the main peak wasnot sharp but showed multiple smaller peaks indicating a dough-liketexturation.

E denotes the end point of each measurement. When the compressionreached 99% strain, the loading (compression) was ended and drawn backso that the resistance force drops to 0.

The resistance force N and penetration distances correspond with biteresistance that is required to break down the structure of the texturedfood product and are extremely important acceptability/quality parameterof textured food product, and there is a window of texture associated byconsumers with various protein-based products. For example, the rate atwhich the product breaks down on chewing, the number of chews requiredbefore the material can be swallowed, the textures exposed to the teethand tongue during chewing are all important in determining theacceptability of the product, especially in the case of presentinvention where the textured food product is used as ready-to-eatproduct that can be consumed as a snack or as heat- and boilingresistant cookable main course food. The fibrous structure of thetextured food product provides very acceptable mouthfeel, desirablechewiness and juiciness, and a feeling of real food when consumed as asnack or cookable main course food.

Penetration distance (mm) needed to break down the textured structuresignificantly decreased while adding oat protein in the structure.

FIG. 3 is a photograph showing the structure of sample 3. As we can seefrom FIG. 3, the structure is solid and does not contain significant orhighly visible pores or air bubbles.

FIG. 4 is a photograph showing the structure of sample 1. As we can seefrom FIG. 4, the structure is porous; this results from oat bran in theslurry. The feature is well known and commercially utilized, and iscreated by starch that oat bran contains. The feature is often desiredto layer the product and modify the mouthfeel, and starch is used inseveral commercial soy texturates in level of 5%. Oat bran contains 50%of starch, which explains the phenomenon well.

When starch is added in relatively high levels as in the present method,and especially with other interfering components such as fibre (˜14% inoat bran) and oil bodies (˜8% in oat bran), the desired fibrous textureand bite resistance is ruined (cf. the description of the measurementthe results of which are shown in FIG. 2 and discussed above).

This is in line with the measurements the results of which are shown inFIG. 2. For our sample 3, the porous texture is more moderate and thebite resistance much higher than for sample 1.

Without wishing to be bound by any theory, it is thought that this maybe due to the hydrophobic nature of the oat proteins opposite to thelegume proteins that are excellent emulsifiers and foaming agents. Theoat proteins break the bubble texture caused by starch rapidgelatination in the cooling stage, reduce the level of gelatination,water evaporation induces mass expansion and the escape of oats' solublefibres, which both can create the unwanted slimy surfaces into thetexture. When the gas bubbles are not interfering the protein-proteinlinkages, the texture is less porous, force required to break texturedfood product increases and water absorption rates and hydration levelsare reduced.

FIG. 5 shows the microscopic structure of an extruded textured foodproduct of the second sample as captured by an electron microscope. Thefibrous structure consists of thick (between 20 and 30 μm) fibres thatare bunched together and oriented multi-directionally. The fibroustexture is soft, slimy and gives a dough-like mouthfeel.

FIG. 6 shows the microscopic fibrous structure of a fourth sample thatwas a extruded textured food product which contains pea protein, 20% ofoat bran and 10% of oat protein, as captured by an electron microscope.The fibrous structure consists of relatively thick (between 15 and 20fibres that co-aligned and and bunched together. The structure iscomparable with meat and gives a pleasant and soft meat-like mouthfeel.

FIG. 7 shows the microscopic structure of a fifth sample that was anextruded textured food product containing pea protein only, as capturedby an electron microscope. The structure consist of very long,hair-like, branched and very fine continuos bunches of fibres. We haveobserved that this kind of structure is not easy to swallow and gives ahairy mouthfeel.

FIG. 8 shows the fibrous structure of a sixth sample that was anextruded hydrated textured food product containing pea protein, 20% oatbran and 10% of oat protein, captured by a microscope. The fibres in thesixth sample are 10 times thicker than in a seventh sample that was anextruded textured food product which contains only legume protein.

FIG. 9 is a photograph showing a serving of consumer-ready textured foodproduct 92 which contains legume protein (especially pea), oat bran andoat protein, placed on a cutting board 91. A vicia faba pods and seeds93 and a dried oat plant 94 are also shown to illustrate the dimensions.

The soft but fibrous structure of the textured food product 92 gives avery acceptable mouthfeel, a desirable chewiness and juiciness, and afeeling of real food when consumed as a snack or as a cooked main coursefood.

With regard to the sliminess of the second sample, we made a viscosityanalysis on the second sample and a seventh sample (the dry matter ofthe slurry contained pea protein, 20 weight-% of oat bran and 20weight-% of oat protein) with a Thermohaake® Rheostress® 600 (both trademarks of Thermo Electron GmbH, Dreieich, Germany) measurement apparatus.A flow curve obtained by using the cone and plate geometry (60 mm, 1°over a shear rate range of 0.3-300 1/s at 21° C.) showed a significantdifference between sample 2 and sample 3. The apparent viscosity at 101/s was 10-20 mPas for the seventh sample and 100-130 for the secondsample. The replacement of a part of the pea protein with oat proteinresults in a significant decrease in the viscosity. This is an indicatorthat the felt sliminess reduces as well.

The legume proteins used in the method may comprise any proteinsdelivered from legumes. A legume is a plant in the family Fabaceae (orLeguminosae), or the fruit or seed of such a plant. Well-known legumesinclude alfalfa, clover, peas, beans, vicia fabas, lentils, lupins,mesquite, carob, soybeans, peanuts and tamarind. We have carried out ourtests with pea based legume proteins, peanut based legume proteins,vicia faba based legume proteins, and with a combination of these.However, we suppose that any of the other mentioned proteins could beused to produce the textured food product of this invention and in themethod accordingly.

Not only the structure of the textured food product manufactured by thepresent method considerably differs from porridges, biscuits, breads,morning cereals, flapjack bars, granolas, noodles, oat rice and mueslis,where oat has previously been used, but also the nutritional values aredifferent.

Oat contains 12-23 weight-% of protein that is a protein contentcomparable with quinoa or other plants having a reputation as goodprotein sources. The amino acid content is better than in any othergrain, thus the lysine content is also high among grains. In addition,oat contains high levels—even more than egg or other animal proteins—ofsulfuric acid (mainly cystine) per protein, which is especially relatedto the good bone healthy. The lysine content that limits the use ofgrain proteins in textured food products is also relatively high inoats. However, it is still low when compared to the legumes and thushigh lysine containing protein from legumes may be desired to balanceoff the relatively low concentration of lysine in the oat protein.

The textured food product according to the present invention will be asource of all essential amino acids isoleucine, leucine, lysine,methionine, phenylalanine, threonine, tryptophan, valine and histidine.

TABLE 2 Sample Quinoa Egg Beef Soy WHO Icoleucine 1239 480 750 1000 8001400 Leucine 2324 840 1100 1700 1400 2730 Lycine 1673 700 900 1800 11502100 Methionine 426 310 440 560 225 1050 Cystine 425 150 260 150 240Phenylalanine 1532 500 710 870 900 1750 Tyrosine 3486 410 560 730 550Threonine 1600 370 600 940 700 1050 Tryptophan 401 1100 180 230 230 280Valine 2279 570 950 1100 850 1820 Arginine 2483 1200 830 1300 1300Histidine 953 360 320 760 455 700 Alanine 1272 530 790 1300 750 Asparticacid 2880 1070 1400 1900 2100 Glutamic acid 5142 1890 1500 3100 3350Glycine 1180 880 460 1100 750 Proline 1352 560 500 870 1000 Serine 1461570 990 870 900

Table 2 shows measured amino acid compositions of a textured foodproduct manufactured with the present method, as compared withliterature [2] values for Quinoa, Egg (whole chicken egg), Beef (rawlean meat) and moistened textured soy. The amino acid content (inmilligrams) taken from 100 g of each product. The values in column WHOrepresent the daily requirements for the essential amino acids(milligrams of amino acid that a person with a weight of 70 kg shouldconsume daily). As can be seen, the textured food product manufacturedaccording to the method of the present invention (37% oats, 33% pea, 25%vicia faba, oil and spices) has a relatively high amount of essentialamino acids.

The soluble fiber content of the textured food products manufacturedwith the present method will be high: a quantified portion (80-120 g)will contain at least 1 g of beta-glucan. That amount enables the healthclaims about maintaining cholesterol levels, lowering blood cholesteroland thereof improving cardiac health [3] [4].

In addition to excellent amino acid and soluble fiber content, thetextured food products of present invention contains oils (1-10%) thatare delivered from oats. Oat contains a relatively high amount of lipidsand best fatty acid composition among grains. It contains relativelyhigh amounts of oil acid and essential linoleic acid.

In the present method, at least 10 weight % of oat protein is used toprepare the slurry. This share of oat protein is sufficient to attainreasonable sulfurous containing amino acids in a quantified portion(80-120 g). If only incorporating oat bran or oat flour to the texturedfood product, the ratio of oat bran or oat flour should be a totalof >55% of all ingredients to attain reasonable sulfurous containingamino acids to the food product in quantified portion (80-120 g). Thiswould dilute the lysine content of the product and also result inunsuitable dough-like structure.

One of the challenges with soya based textured products widely utilizedas a plant based main course is the beany taste of the products thatmakes consumer to search alternatives. Oat, utilized in the presentinvention, serves a mild taste and highly ecological alternative.According to our studies, the mild, grainy taste of oats effectivelyhinders the beany taste of legumes (especially vicia faba and/or pea).The replacement of 10% of the legume protein concentrate with oatprotein concentrate is significant. The beany taste disappears or isvery mild in the product containing 40% of oat materials and 60% of peaprotein concentrate. Also the “oaty” taste of the product is very mildor has completely disappeared.

Method of Manufacturing the Extruded Textured Legume Protein ContainingFood Product Comprising Oat Bran and Oat Protein

The method of manufacturing the textured food product comprising atleast one legume protein, oat bran and oat protein can be illustrated bythe following examples, although it will be understood that theseexamples are included merely for purposes of illustration and are notintended to limit the scope of the invention.

Example 1: Manufacturing of Extruded Textured Legume Protein, Oat Branand Oat Protein Containing Ready-to-Eat Product that can be Consumed asa Snack with 50% of Oats

-   -   Fine flours (the average particle size 320 μm) of oat bran 20%,        oat protein fraction 20%, whole oat flour 10%, vicia faba        protein concentrate 25% and pea protein isolate 25% are mixed        with water to result in 30% water content. The mix is feeded to        a 40 kg capasity twin-screw extruder with a speed of 25 kg/h.        Screw speed of 300 rpm is settled and temperatures profile 60°        C.->175° C.->130° C. used in six temperature sections. The mass        is let shortly to cool in 10 cm long die. Prom extrusion, the        cutted fibrous pieces are moistened and spiced in a drum by        spraying spiced water. The moisture is adjusted to 40%, rapeseed        or other high quality oil is sprayed and salt sprinkled on top,        followed by heating the pieces in oven for 15 minutes (180° C.)        to attain color and crispy surface with chewable core.

Example 2: Manufacturing of Extruded Textured Legume Protein, Oat Branand Oat Protein Containing Main Cource Product

-   -   Fine flours (the average particle size 320 μm) of oat bran 20%,        oat protein fraction 20%, vicia faba protein concentrate 30% and        pea protein isolate 30% are mixed with water to result in 30%        water content. The mix is feeded to a 40 kg capasity twin-skrew        extruder with speed of 25 kg/hour. Screw speed of 300 rpm is        settled and temperatures profile 60° C.->175° C.->130° C. used        in six temperature sections. The mass is let shortly to cool        through 10 cm long die.    -   The cutted fibrous pieces are moistened with mixing up to 54%        moisture with water, salt and spices. The moistened fibres are        mixed with high speed mixer to organic shape pieces, pea and oat        protein are added in a concentration of 6% to the mass. Rapeseed        oil and hydrophobic spices are added during mixing 15 minutes.        After mixing, the pieces are optionally heated under steam and        pressure (1 bar) at 120° C. for 15 minutes. Dry spices are        added, and the products are packed under 80% of CO₂ and 20% of        N₂. The consumer heats the product in a pan with oil or in oven.

Example 3: Manufacturing of Extruded Textured Legume Protein, Oat Branand Oat Protein Containing Product with Further Post Extrusion Treatment

-   -   Fine flours (the average particle size 320 μm) of oat bran 20%,        oat protein fraction 20%, vicia faba protein concentrate 30% and        pea protein isolate 30% are mixed with water to result in 30%        water content. The mix is feeded to a 40 kg capasity twin-skrew        extruder with speed of 25 kg/hour. Screw speed of 300 rpm is        settled and temperatures profile 60° C.->175° C.->130° C. used        in six temperature sections. The mass is let shortly to cool        through 10 cm long die.    -   After extrusion treatment the post extrusion treatment is        carried out by moisturising textured food product with spiced        water where the share of water to the dry material is between        1:1.0 to 1:1.5 and brewed (or, alternatively, hydrated, wetted        or soaked) 2-14 hours before further processing. The brewed (or        alternatively, hydrated, wetted or soaked) product is further        treated with amylase and processed with high speed mixing for        1-60 minutes. After that an additional high pressure cooking        step is performed in an autoclave or in a pressurized cooking        device, preferably having a pressure of at least 1.9 bar, and        preferably for 20 to 60 minutes (even more preferably, for        around 25 minutes or between 30 to 60 minutes), such as for 35        to 45 minutes. Instead of the high pressure cooking step, the        treated product may be baked or cooked in a baking or cooking        step, preferably in an oven or in a steam oven, in a temperature        between 110 and 130° C., most preferably around 121° C.    -   Surprisingly, this post extrusion treatment further improves        pleasant sensory properties of the textured food products.    -   We are at the time of writing experimenting with a product in        which the share of water to the dry material is essentially        about 1:3.

Although the examples above show the use of twin-screw extruder, itshould be understood that extrusion processes are very diverse andmanufacturing of extruded textured legume protein, oat bran and oatprotein containing product can be prepared via use of any acceptablemodel of type food processing extruder, both with single screw or withtwin screw types.

At the time of writing, the applicant is carrying out research workwhether oat could at least partly (or even completely) be replaced withrye and/or barley. In this case, a) oat bran could be replaced (at leastpartly, or even completely) with rye bran and/or barley bran; b) wholegrain oat flour could be replaced (at least partly, or even completely)with whole grain rye flour and/or whole grain barley flour; andrespectively c) the mixture of oat bran and whole grain oat flour couldbe replaced (at least partly, or even completely) with mixture of ryebran and/or barley bran and whole grain rye flour and/or whole grainbarley flour.

Respectively, research work is being carried out by the presentapplicant, whether oat protein fractions could be replaced at leastpartly (or even completely) with rye protein fractions and/or barleyprotein fractions.

A first exemplary process is:extruding->brewing/hydrating/wetting/soaking (such that the ratio ofwater to the textured food product is between 1:1.0 to 1:1.5)->mixingand adding spices->autoclaving (such as for 30 minutes and preferably ataround 2 bar).

A second exemplary process is:extruding->brewing/hydrating/wetting/soaking (such that the ratio ofwater to the textured food product is about 1:1.3) preferably withspices, drying (preferably in oven), spraying with cooking oil, addingsalt (preferably by sprinkling).

After the first or the second exemplary process, the thus processedtextured food product can be packed.

At the time of writing, we are experimenting whether the cooking oil cancould be added already in the brewing/hydrating/wetting/soaking step.Therefore, the spraying with cooking oil must be considered as anoptional step.

It is obvious to the skilled person that, along with the technicalprogress, the basic idea of the invention can be implemented in manyways. The invention and its embodiments are thus not limited to theexamples described above but they may vary within the contents of patentclaims and their legal equivalents.

REFERENCES

-   [1] Harper, J. M. 1979. Extruder not prerequisite for texture    formation. J Food Sci 44: ii.-   [2] Danish Food Composition Databank—ed. 7.01    (http://www.foodcomp.dk/v7/fcdb_search.asp)-   [3] EFSA Journal 2011; 9(6):2207-   [4] EFSA Journal 2010; 8(12):1885

List of reference numerals used: 91 cutting board 92 serving of texturedfood product 93 vicia faba seed 94 dried oat plant

1. A method of manufacturing a textured food product, comprising thesteps of: preparing a slurry comprising dry matter and water, i) whereinthe dry matter comprises:
 1. at least 35% by weight legume protein, 2.10% to 45% by weight oat bran, whole grain oat flour or a mixturethereof, and
 3. 2% to 35% by weight of the dry matter of oat protein, ofwhich
 2. and
 3. must always add up to no more than 65% by weight; andii) wherein the slurry further comprises water 20%-80% by weight of theweight of the dry matter; and cooking the slurry in an extruder cooker;and extruding the cooked slurry to form said textured food product. 2.The method according to according to claim 1, wherein: the step ofcooking is performed at a temperature between 130° to 191° C.
 3. Themethod according claim 1, wherein: the share of oat bran and of oatprotein is 40% to 60% by weight of the dry matter weight of the slurryand is preferably selected to produce a textured food product having aconsistency for which a resistance force exhibited by 9.0 to 10.5 mmhigh sample of said textured food product during a compression test witha knife blade required to cut the sample textured food product isbetween 16 N and 28 N with a penetration distance between 5.5 and 8.5mm.
 4. The method according to claim 1, wherein: after the step ofextruding the cooked slurry to form said textured food product, thetextured food product is further processed with water, salt, oil andspices and brewed, hydrated, wetted or soaked before performing anadditional baking, cooking or high pressure cooking step on said furtherprocessed textured food product. Preferably, water, oil and spices aresprayed at the textured food product and salt is sprinkled.
 5. Themethod according to claim 4, wherein: during the brewing, hydration,wetting or soaking step, the ratio of water to the textured food productis between 1:1.0 to 1:3 by weight, preferably between 1:1.0 to 1:1.5 byweight, or essentially about 1:3 by weight.
 6. The method according toclaim 4, wherein: amylase is added to the textured food product afterthe extruder cooking step but before the additional high pressurecooking step.
 7. The method according to claim 4, wherein: theadditional high pressure cooking step is performed in an autoclave or ina pressurized cooking device, preferably at a pressure of at least 1.9bar, most preferably at 2 bar, and preferably for between 20 to 60minutes, or for between 30 to 60 minutes.
 8. The method according toclaim 4, wherein: the step of brewing, hydrating, wetting or soaking iscarried out for at least 10 minutes, preferably between 2 to 12 h. 9.The method according to claim 1, wherein: the dry matter of oat proteinis as at least one oat protein fraction, or a plurality of oat proteinfractions.
 10. The method according to claim 1, wherein: the legumeprotein introduced into the slurry is selected from at least one of thefollowing: pea protein concentrate, pea protein isolate, vicia fabaprotein concentrate, vicia faba protein isolate, peanut proteinconcentrate, peanut protein isolate.
 11. The method according to claim1, wherein: the step of extruding is carried out as a proteintexturation extrusion.
 12. The method according to claim 10, wherein: awater feed rate during the step of extruding and other extruding stepparameters are selected such that the textured food product will resultco-aligned fibres that are bunched together and that are relativelythick, preferably having a thickness of between 15 and 20 μm.
 13. Themethod according to claim 1, wherein: the percentage of oat protein ischosen to compensate for effects leading to a dough-like texturation ofthe textured food product due to the percentage of oat bran, whole grainoat flour or the mixture thereof in the dry matter.
 14. The methodaccording to claim 1, wherein: said water in said slurry comprisesbetween 28% and 40%, preferably between 30% and 40%, by weight of thedry matter. The percentage of water preferably includes water/humidityin the flour.
 15. The method according to claim 1, wherein: said waterin said slurry comprises between 35% and 40% by weight of the drymatter. The percentage of water preferably includes water/humidity inthe flour.
 16. The method according to claim 1, wherein: the step ofcooking is performed at a temperature in the range of between 170° C. to191° C.
 17. The method according to claim 1, wherein: the step ofcooking is performed essentially at a temperature of about 175° C. 18.The method according to claim 1, wherein: the step of cooking isperformed at a temperature between 130° C. to 180° C.
 19. The methodaccording to claim 3, wherein: said penetration distance is between 7.5and 8.5 mm.
 20. The method according to claim 4, wherein: said water,oil and spices are sprayed at the textured food product and said salt issprinkled on said textured food product.
 21. The method according toclaim 10, wherein: at least 35% of legume protein is computed from theprotein fraction of the respective legume protein or legume proteinsintroduced into the slurry.
 22. The method according to claim 1,wherein: the dry matter comprises 5% to 35% by weight of the dry matterof oat protein.
 23. The method according to claim 1, wherein: said oatbran, said whole grain oat flour or said mixture thereof is replacedwith barley bran and/or whole grain barley flour or a mixture thereof.24. The method according to claim 1, wherein: said oat bran and/or saidwhole grain oat flour or said mixture thereof is replaced with rye branand/or whole grain rye flour or a mixture thereof.
 25. The methodaccording to claim 1, wherein: the dry matter comprises: 10% to 45% byweight of: i) oat bran, whole grain oat flour, or a mixture of oat branand whole grain oat flour, ii) barley bran, whole grain barley flour, ora mixture of barley bran and whole grain barley flour, iii) rye bran,whole grain rye flour, or a mixture of rye bran and whole grain ryeflour, or iv) a mixture of at least two or three of the ingredientslisted under i) to iii)
 26. The method according to claim 1, wherein:the oat protein is at least partly replaced with rye protein and/orbarley protein.
 27. The method according to claim 1, wherein: thepercentage of oat protein in the dry matter is taken as a percentage ofoat protein fraction or fractions in the dry matter.
 28. The methodaccording claim 1, wherein: the percentage of oat protein in the drymatter is taken as the sum of a percentage of the matter under nr. 2.and of the percentage of oat protein fraction or fractions in the drymatter.
 29. A textured food product, manufactured according to themethod according to claim
 1. 30. The textured food product according toclaim 29, wherein: the percentage of oat protein is chosen to produce atextured food product having an apparent viscosity between 10 and 20mPas at 10 1/s.
 31. The method according to claim 1, wherein: thepercentage of oat protein is chosen to produce a textured food producthaving water absorption rate of less than 70% water level in 120minutes.
 32. A method of manufacturing a textured food product,comprising the steps of: preparing a slurry comprising dry matter andwater, i) wherein the dry matter comprises:
 1. at least 35% by weightlegume protein,
 2. 10% to 45% by weight oat bran, whole grain oat flouror a mixture thereof, and
 3. 2% to 35% by weight of the dry matter ofoat protein, of which
 2. and
 3. must always add up to no more than 65%by weight, and wherein the percentage of oat protein is chosen toproduce a textured food product having an apparent viscosity less than20 mPas at 10 1/s; and ii) wherein the slurry further comprises water20%-80% by weight of the weight of the dry matter; and cooking theslurry in an extruder cooker; and extruding the cooked slurry to formsaid textured food product.
 33. A method according to claim 32, wherein:the percentage of oat protein is chosen to produce a textured foodproduct having an apparent viscosity between 10 and 20 mPas at 10 1/s.34. A method of manufacturing a textured food product, comprising thesteps of: preparing a slurry comprising dry matter and water, i) whereinthe dry matter comprises:
 1. at least 35% by weight legume protein, 2.10% to 45% by weight oat bran, whole grain oat flour or a mixturethereof, and
 3. 2% to 35% by weight of the dry matter of oat protein, ofwhich
 2. and
 3. must always add up to no more than 65% by weight,wherein the percentage of oat protein is chosen to produce a texturedfood product having water absorption rate of less than 70% water levelin 120 minutes; and ii) wherein the slurry further comprises water20%-80% by weight of the weight of the dry matter; and cooking theslurry in an extruder cooker; and extruding the cooked slurry to formsaid textured food product.
 35. The method of improving the structure ofa textured food product, wherein: an amount of legume protein in aslurry comprising water and dry matter of oat bran, rye bran, barleybran, whole grain oat flour, whole grain rye flour, whole grain barleyflour, or a mixture thereof, and of legume protein is replaced with oatprotein, rye protein, barley protein or mixture thereof before cookingthe slurry in an extruder cooker and extruding the cooked slurry to formsaid textured food product.
 36. The method of claim 35, wherein: the drymatter used to prepare the slurry comprises at least 10 weight-% of oatprotein, rye protein, barley protein or mixture thereof.
 37. The methodaccording to claim 36, wherein: in the dry matter, the oat/rye/barleybran or whole grain flour with the replacement protein must always addup to no more than 65% by weight.
 38. The method according to claim 35,wherein: the percentage of oat protein is chosen to produce a texturedfood product having an apparent viscosity less than 20 mPas at 10 l/s.